采购提交与报销新建/提交事务显式使用10秒上限 [09-27-purchase-submit-tx-timeout]

负载下采购提交事务超过 Prisma 交互事务默认 5000ms（P2028）返回 500。
分段计时显示无单一瓶颈（总时长中位 843ms、最大 3506ms，编号锁等待
最多 535ms），是约 20 条顺序查询整体变慢贴近上限。报销新建/提交同结构。
三处改用项目既有的 { maxWait: 5000, timeout: 10000 }，事务内容不变；
新增采购与报销提交的事务选项回归断言。

Co-Authored-By: Claude Opus 5.5 <[email protected]>

.trellis/tasks/09-27-purchase-submit-tx-timeout/implement.md

@@ -0,0 +1,7 @@
+## 2026-09-27 实施（当前）
+
+- [x] 临时分段计时（未提交，已还原）定位：事务总时长中位 843ms/最大 3506ms，无单一瓶颈，编号锁等待最多 535ms。
+- [x] 采购提交、报销新建、报销提交三处 `$transaction` 显式 `{ maxWait: 5000, timeout: 10000 }`；事务内容不变。
+- [x] 回归断言：采购提交（去掉修复即失败）、报销提交。
+- [x] 后端全量单测：4451 通过 / 1 原跳过。
+- [ ] 负载复现确认无采购提交 P2028；随下次发布候选走完整门禁。

.trellis/tasks/09-27-purchase-submit-tx-timeout/prd.md

@@ -0,0 +1,33 @@
+# 采购提交事务负载下超时返回500
+
+## Goal
+
+消除采购提交（及同结构的报销新建/提交）在负载下超过 Prisma 交互事务默认 5000ms 上限而返回 500（P2028）的问题。
+
+## Background / Evidence（2026-09-26/27）
+
+- 09-26 负载复现（采购 ×6–8 + permission-direct-access ×6–8，4 worker，2 核主机）每轮出现 1–2 次 `purchase submit failed: 500`，服务端为 `P2028 Transaction API error ... timeout 5000 ms, 5352 ms passed`，位于 `server/src/routes/purchaseRequests.js` 提交事务内的 `workflowTask.create`。正式门禁 6 轮未出现。
+- 生产 `b1d25d3c` 与当前代码同写法（默认超时），非近期回归。
+- 09-27 事务内分段计时（16 次提交全部成功）：锁定单据中位 41/最大 290ms；编号前校验与预检 466/1659ms；编号分配含锁等待 101/535ms；编号后至提交 317/2194ms；**事务总时长中位 843ms、最大 3506ms**。无单一瓶颈：编号行锁等待最多 0.5s，主要是约 20 条顺序查询在负载下整体变慢，贴近 5s 上限。
+- 报销新建（`POST /reimbursements`）与提交（`/reimbursements/:id/submit`）同样在默认超时事务内分配编号、执行多步写入，属同一风险。
+
+## Scope
+
+- 采购提交、报销新建、报销提交三处交互事务显式使用项目既有写法 `{ maxWait: 5000, timeout: 10000 }`（付款批次、回执 OCR 等已采用）。
+- 不改事务内容、顺序、锁、编号或业务语义。
+
+## Out of Scope
+
+缩短编号行持锁时间的重排、其他路由事务的统一治理、部署。
+
+## Acceptance Criteria
+
+- [ ] 三处事务传入 `{ maxWait: 5000, timeout: 10000 }`，采购与报销提交各有回归断言（去掉修复即失败）。
+- [ ] 后端全量单测通过。
+- [ ] 负载复现不再出现采购提交 P2028。
+
+## Test Plan
+
+- `server/tests/unit/routes/purchase.submit-budget-precheck.test.js`：新增断言提交事务选项；已验证去掉修复时该用例失败。
+- `server/tests/unit/routes/reimbursements.expense-standards.test.js`：在既有成功提交用例中断言事务选项。
+- 后端全量 vitest；负载复现脚本（见 09-26-approve-success-state-unchanged/research/repro.sh）。

.trellis/tasks/09-27-purchase-submit-tx-timeout/task.json

@@ -0,0 +1,33 @@
+{
+  "id": "purchase-submit-tx-timeout",
+  "name": "purchase-submit-tx-timeout",
+  "title": "采购提交事务负载下超时返回500",
+  "description": "负载复现中采购提交交互事务超过Prisma默认5000ms（P2028）返回500；生产b1d25d3c起同写法。查清耗时构成（锁等待/事务内查询），给出最小修复。",
+  "status": "planning",
+  "dev_type": null,
+  "scope": "transaction-timeout",
+  "package": null,
+  "priority": "P2",
+  "creator": "shunli",
+  "assignee": "shunli",
+  "createdAt": "2026-09-27",
+  "completedAt": null,
+  "branch": null,
+  "base_branch": "main",
+  "worktree_path": null,
+  "commit": null,
+  "pr_url": null,
+  "subtasks": [],
+  "children": [],
+  "parent": null,
+  "relatedFiles": [
+    "server/src/routes/purchaseRequests.js",
+    "server/src/routes/reimbursements.js",
+    "server/tests/unit/routes/purchase.submit-budget-precheck.test.js",
+    "server/tests/unit/routes/reimbursements.expense-standards.test.js"
+  ],
+  "notes": "",
+  "meta": {
+    "implementationApproval": "APPROVED_BY_USER_20260927"
+  }
+}

server/src/routes/purchaseRequests.js

@@ -1701,6 +1701,8 @@ async function purchaseRequestRoutes(fastify, options = {}) {
         throw buildBusinessValidationError("purchase_request.approver_unavailable", { workflow: "no_actionable_approver" }, 409);
       }
 
+      // ~20 sequential queries plus document numbering; under load this exceeded
+      // Prisma's 5s interactive-transaction default (P2028 -> 500).
       const submitResult = await fastify.prisma.$transaction(async (tx) => {
         const locked = await loadPurchaseRequestForUpdate(tx, purchaseRequestId);
         ensureDraftOwner(request, locked);
@@ -1949,7 +1951,7 @@ async function purchaseRequestRoutes(fastify, options = {}) {
             budgetReservation,
           },
         };
-      });
+      }, { maxWait: 5000, timeout: 10000 });
 
       void fastify.prisma.auditLog.create({
         data: buildAuditLogData(request, {

server/src/routes/reimbursements.js

@@ -1863,7 +1863,7 @@ async function reimbursementRoutes(fastify) {
           ...created,
           items: createdItems,
         };
-      });
+      }, { maxWait: 5000, timeout: 10000 });
 
       return sendData(reply, request, {
         id: reimbursement.id,
@@ -4498,7 +4498,7 @@ async function reimbursementRoutes(fastify) {
             actorId: request.employee.id,
           },
         };
-      });
+      }, { maxWait: 5000, timeout: 10000 });
 
       await finalizeReimbursementSubmitSideEffects({
         prisma: fastify.prisma,

server/tests/unit/routes/purchase.submit-budget-precheck.test.js

@@ -315,6 +315,17 @@ describe("purchase request submit budget precheck gate", () => {
 
     await app.close();
   });
+
+  it("runs the submit transaction with a 10s budget instead of Prisma's 5s default", async () => {
+    resolveEntityPrecheckMock.mockResolvedValue(buildPrecheck({ budgetHint: { controlMode: "block" } }));
+    const { app, prisma } = await buildApp({ budgetControlMode: "warn", budgetPrecheckEnabled: false });
+
+    const response = await app.inject({ method: "POST", url: `/api/purchase-requests/${PURCHASE_REQUEST_ID}/submit` });
+
+    expect(response.statusCode).toBe(200);
+    expect(prisma.$transaction).toHaveBeenCalledWith(expect.any(Function), { maxWait: 5000, timeout: 10000 });
+    await app.close();
+  });
 });
 
 it.each([1, 2])("submits a stored v%s purchase draft under active policy without reclassifying it", async (version) => {

server/tests/unit/routes/reimbursements.expense-standards.test.js

@@ -325,7 +325,7 @@ describe("reimbursements routes expense standard integration", () => {
 
   it.each([true, false])("avoids unused bound-invoice counts: per-item guard=%s", async invoiceGuardEnabled => {
     resolveEntityPrecheckMock.mockResolvedValue(buildPrecheck());
-    const { app, tx } = await buildApp({ invoiceGuardEnabled, reimbursementItems: [{
+    const { app, prisma, tx } = await buildApp({ invoiceGuardEnabled, reimbursementItems: [{
       id: "item-no-invoice", amount: "180.00",
       expense_type: { code: "office", category: "office", requires_invoice: invoiceGuardEnabled },
     }] });
@@ -336,6 +336,8 @@ describe("reimbursements routes expense standard integration", () => {
       expect(tx.reimbursementItem.findFirst).not.toHaveBeenCalled();
       expect(tx.reimbursementItem.aggregate).toHaveBeenCalledTimes(1);
       expect(tx.workflowHistory.create).toHaveBeenCalled();
+      // Prisma's 5s interactive-transaction default was exceeded under load (P2028 -> 500).
+      expect(prisma.$transaction).toHaveBeenCalledWith(expect.any(Function), { maxWait: 5000, timeout: 10000 });
     } finally { await app.close(); }
   });